Diarrhea may be caused by:

  • Food intolerance, such as lactose intolerance
  • Some medicines, such as:
    • Antibiotics
    • Antacids that have magnesium in them
    • Chemotherapy
    • Laxatives
  • Irritable bowel syndrome
  • Injury to the bowel after radiation treatments for cancer
  • Malabsorption syndromes, such as celiac disease
  • Diseases of the pancreas or gallbladder
  • Inflammatory bowel diseases, such as ulcerative colitis and Crohn disease
  • Chronic diseases, such as:
    • Liver disease
    • Diabetes
    • Hyperthyroidism
    • AIDS
    • Colon cancer
  • Intestinal surgery
  • Infections such as:
    • Bacterial, such as salmonella
    • Viral, such as rotavirus and norovirus
    • Parasitic
    • Fungal, such as yeast

Risk Factors

Things that may raise the risk of diarrhea are:

  • Traveling to a country where the water and food supply may be contaminated
  • Taking certain medicines
  • Being in a hospital
  • Having a severely weakened immune system, such as with AIDS or after an organ transplant



A person may have:

  • Frequent loose, liquid stools
  • Belly pain and cramping
  • An urgent need to have a bowel movement
  • Blood and mucus in the stool
  • Fever
  • Nausea and vomiting
  • Muscle aches and pains
  • Weight loss

When Should I Call My Doctor?

Call the doctor if you:

  • Have diarrhea that lasts longer than three days
  • Are not able to eat or drink to stay hydrated
  • Have a fever

Call the doctor if your young child:

  • Has diarrhea that lasts longer than a day
  • Has pus in his or her stool
  • Does not have wet diapers
  • Is crying without tears
  • Is unusually sleepy or irritable
  • Has a fever

When Should I Call for Medical Help Right Away?

Call for medical help or go to the emergency room right away if you or your child has:

  • Severe belly pain and cramping
  • Bloody or black stool


The doctor will ask about symptoms and health history. A physical exam will be done. The doctor may insert a gloved finger into the rectum to examine it. This is called a digital rectal exam.

The doctor may ask some questions to find the cause of diarrhea:

  • Does anyone else in the family have diarrhea?
  • What kinds of food and drinks have you had?
  • Do your children attend daycare?
  • Have you traveled recently?
  • What is your sexual history?

Blood tests and stool tests may be done.

The rectum and colon may need to be checked. This can be done with:

  • Flexible sigmoidoscopy
  • Colonoscopy

A biopsy may also be taken.

Images may be taken of the colon. This can be done with:

  • Upper gastrointestinal (GI) series
  • Barium enema
Barium Enema
Radiology colon
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The goal of treatment is to ease diarrhea and prevent dehydration. Any underlying cause will need to be treated.

Some treatment options are:

  • An oral rehydration solution to replace lost fluids
  • Diet changes, such as a clear diet and avoiding foods that trigger diarrhea
  • Antidiarrheal medicine
  • Probiotics


The risk of diarrhea may be lowered by:

  • Practicing proper hand hygiene
  • Practicing safe food preparation and storage
  • Taking care when traveling, such as:
    • Drinking bottled water and avoiding drinks with ice
    • Avoiding foods from street vendors
    • Not eating raw vegetables or fruits
    • Cooking foods well
    • Only eating pasteurized dairy products

Rotavirus is a common cause of diarrhea in children under 5 years of age. The rotavirus vaccine can prevent it.

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

Edits to original content made by Denver Health.